Two of the three consortia bidding for control of London Underground lines could be paid up to £300 million in success fees and recovered costs as soon as contracts have been signed.

Tube Lines and Metronet are both seeking payment of approximately £109 million immediately after contracts have been signed, and £60 million slightly later.

Shadow transport secretary, Theresa May, said the payments were "yet another incredible development in an altogether strange bidding process".

Transport commissioner for London, Bob Kiley, described the payments as "inexcusable".